Technique of Time Depend Dielectric Breakdown for the Wafer-Level Testing of Thin Dielectrics of MIS Devices

Abstract

Abstract—

The paper proposes a novel technique of time depend dielectric breakdown for the wafer-level testing of thin dielectric of MIS devices based on concatenation of J-Ramp and Bounded J-Ramp methods. The suggested method enhances the existing method capabilities by introducing measurement injection modes. When DUT is under the measurement mode, the charge injection into the gate dielectric is realized under constant current density J_m at which any significant charge degradation of dielectric is not observed. Introduction of the measurement modes give an opportunity to monitor a change of the charge state of thin gate dielectric during all the test. The suggested test is started similar to Bounded J-Ramp method and then in order to raise the monitoring speed, the value of bounded current J_b could be step wisely increased over certain time intervals which are much longer in time in comparison with J-Ramp method. As a result, the charge injection into the gate dielectric could be implemented under multiple J_b values. This test algorithm gives an opportunity to greatly enhance functional capabilities of the existing test methods and the suggested technique raises speed to test.